package com.example.rjwmproject.filter;

import com.alibaba.fastjson.JSON;
import com.example.rjwmproject.common.BaseContext;
import com.example.rjwmproject.common.R;
import lombok.extern.slf4j.Slf4j;
import org.springframework.util.AntPathMatcher;

import javax.servlet.*;
import javax.servlet.annotation.WebFilter;
import javax.servlet.http.HttpServlet;
import javax.servlet.http.HttpServletRequest;
import javax.servlet.http.HttpServletResponse;
import java.io.IOException;

//检查用户是否完成登录
@WebFilter(filterName = "loginCheckFilter",urlPatterns = "/*")
@Slf4j
public class LoginCheckFilter implements Filter {

//    路径匹配器，支持通配符
    public static final AntPathMatcher PATH_MATCHER=new AntPathMatcher();

    @Override
    public void doFilter(ServletRequest servletRequest, ServletResponse servletResponse, FilterChain filterChain) throws IOException, ServletException {
        HttpServletRequest request=(HttpServletRequest) servletRequest;
        HttpServletResponse response=(HttpServletResponse) servletResponse;
//        1.获取本次请求的URI
        String requestURI = request.getRequestURI();

        log.info("拦截到请求:{}",requestURI);

        //定义不需要处理的请求路径
        String[] urls=new String[]{
                "/employee/login",
                "/employee/logout",
                "/backend/**",
                "/front/**",
                "/common/**",
                "/user/sendMsg",
                "/user/login"
        };

//        2.判断本次请求是否要处理
        boolean check = check(urls, requestURI);

//        3.如不需处理，则直接放行
        if(check){
            log.info("本次请求{}不需要处理",requestURI);
            filterChain.doFilter(request,response);
            return;
        }

//        4-1.判断登陆状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("employee")!=null){
            log.info("用户已登陆,用户id为：{}",request.getSession().getAttribute("employee"));

            Long empId=(Long) request.getSession().getAttribute("employee");
            BaseContext.setCurreanId(empId);

            filterChain.doFilter(request,response);
            return;
        }

        //        4-2.判断登陆状态，如果已登录，则直接放行
        if(request.getSession().getAttribute("user")!=null){
            log.info("用户已登陆,用户id为：{}",request.getSession().getAttribute("user"));

            Long userId=(Long) request.getSession().getAttribute("user");
            BaseContext.setCurreanId(userId);

            filterChain.doFilter(request,response);
            return;
        }

        log.info("用户未登录");

//        5.如果未登录则返回未登录结果,通过输出流的方式向客户端页面响应数据
        response.getWriter().write(JSON.toJSONString(R.error("NOTLOGIN")));
        return;
    }

//    路径匹配，检查本次请求是否要放行
    public  boolean check(String[] urls,String requestURI){
        for (String url : urls) {
            boolean match = PATH_MATCHER.match(url, requestURI);
            if(match){
                return true;
            }
        }
        return false;
    }
}
